A sky-blue-and-white Silverado pickup with three big black hydrogen tanks filling the bed was drawing onlookers Monday in front of the Riviera Theatre on King Street in downtown Charleston.

It was part of a Southern Legislative Conference presentation highlighting the progress and the challenges of hydrogen-fuel research.

Hydrogen fuel is expanding into more niche markets, and South Carolina has a network of experts poised to translate that into more state jobs, according to S.C. Hydrogen & Fuel Cell Alliance Executive Director Shannon Baxter-Clemmons.

The alliance is a public-private partnership that includes more than a dozen companies and schools, including the University of South Carolina, Clemson University and South Carolina State University. The group, which also includes the Savannah River National Laboratory and the South Carolina Research Authority, is collaborating to advance the commercialization of hydrogen and fuel cell technologies.

State taxpayers have chipped in more than $12 million for hydrogen fuel cell efforts, while federal, municipal and private sources have invested an additional $115 million in South Carolina.

The Silverado was an early demonstration model, brought out almost three years ago. Hydrogen fuels a modified internal-combustion engine. The major manufacturers have been experimenting with cars that use hydrogen fuel cells and run like electric cars.

Researcher Scott Greenway of Columbia was standing by the truck Monday, explaining to bystanders how hydrogen is more energy-efficient than gasoline and emits only water vapor.

Mike Sandbrink, a tall, burly Kentucky state trooper who reconstructs accidents, stepped up with a question.

"What happens if this thing gets slammed in the rear end?" Sandbrink asked.

The carbon-fiber tanks have been slammed, dropped, even shot with guns without breaking, Greenway said. They have a valve that lets out the gas when severely bumped, and the hydrogen dissipates in the air in about five minutes.

"We have permission to park this under the Capitol in Columbia," he said.

Roy Brandon, a downtown tour guide, stepped up and started taking pictures.

"I just like the fact that it's clean out of the exhaust," he said.

The hydrogen in the tanks was made from natural gas, a process that emits carbon dioxide, although only half as much as a gasoline engine. Researchers are developing ways to get hydrogen from other sources that don't pollute, Greenway said.

For example, a solar panel can produce hydrogen that can be stored for power. To demonstrate, Greenway is rigging up solar panels and hydrogen cells at Fort Sumter. When the conversion is complete, probably by the end of the year, the Civil War landmark will run entirely on the sun and hydrogen.

Critics say hydrogen fuel cells are too expensive, are not energy-efficient and that other technologies may offer better solutions. Other obstacles include the storage and distribution of hydrogen.

Still, in a nation looking for alternatives to fossil fuels, hydrogen also is making inroads as backup power for cell-phone towers and for forklifts in manufacturing plants, Greenway said.

"Are the investments we're making in hydrogen worth it?" he asked. "They're starting to pay off for us."

Trulite President Ron Seftick was demonstrating a backup generator that uses hydrogen fuel cells. For example, hospitals will use it to keep ventilators and other machinery running when the electricity goes out. Trulite opened a plant in Columbia this spring. The operation could mean 1,000 direct and spinoff jobs, company and development officials said when the plant was announced several months ago.

The 20-pound KH4 generator runs on a hydrocell about the size of a liter bottle. The hydrocell contains sodium borohydride, a powder that releases hydrogen when water is poured in.